Non-gravitational infusion set

ABSTRACT

A pressure-applying device for use in an infusion set for feeding blood, saline solution or other fluids from a compressible bag to a catheter or needle for administration to a patient. The device comprises at least a pair of highly resilient, arcuate shaped metallic plates pivoted along their adjacent edges and drawn together along their free edges by buckles or clasps. When pivoted into facing relation the adjacent convex surfaces of the plates act to squeeze fluid from the compressible bag when positioned therebetween. Use of the device obviates the necessity to elevate the infusion bag during use, since infusion is effected by positive pressure rather than by gravity alone.

Leibinsoh 1 Dec. 25, 1973 NON-GRAVITATIONAL INFUSION SET [76] Inventor:Saul Leibinsoh, ll Hagardom St.,

Rishon Lezion, Israel [22] Filed: Apr. 8, 1971 21 Appl. No.: 132,516

Related US. Application Data [63] Continuation-in-part of Ser. No.753,405, Aug. 19,

i968, Pat. N0. 3,595,232.

[52] [1.8. CI. 128/214 F, l28/DIG.' 12, 222/336 Braley 128/402 Freedman222/l03 Primary Examiner-Richard A. Gaudet Assistant Examiner-J. C.McGowan Attorney-Ostrolenk, Faber, Gerb & Soffen 57] ABSTRACT Apressure-applying device for use in an infusion set for feeding blood,saline solution or other fluids from a compressible bag to a catheter orneedle for administration to a patient. The device comprises at least apair of highly resilient, arcuate shaped metallic plates pivoted alongtheir adjacent edges and drawn together along their free edges bybuckles or clasps. When pivoted into facing relation the adjacent convexsurfaces of the plates act to squeeze fluid from the compressible bagwhen positioned therebetween. Use of the device obviates the necessityto elevate the infusion bag during use, since infusion is effected bypositive pressure rather than by gravity alone.

2 Claims, 13 Drawing Figures PATENTEU 3.780.732

SHEET 1 0F 4 NON-GRAVITATIONAL INFUSION SET BACKGROUND OF THE INVENTIONThis application is a continuation-in-part of my application, Ser. No.753,405, filed Aug. 19, 1968, now US. Pat. No. 3,595,232 granted July27, 1971, and is directed to an improved form of the infusion devicethereof.

The present invention relates to infusion apparatus, and moreparticularly to a novel sterile fluid infusion set of thenon-gravitational type which is adapted to provide positive fluid flowfor infusion, regardless of the relative positioning of the infusion setwith regard to the patient. The infusion set may be provided with a dripchamber which prevents air from entering into the flow of the exitingfluid even in cases where the orientation of the drip chamber may becomeaccidentally altered during use.

Infusion apparatus finds widespread use in the medical field. Forexample, when it is desired to infuse blood or other sterile fluids intothe body of a patient being treated, the fluid to be introduced into thebody is typically'fed from a suitable container (e.g., of glass orplastic) supported a predetermined distance above the patients body,infusion being effected by gravity flow. in military or other fieldapplications when, for example, the patient is carried on a stretcher anextra person is needed to hold the infusion bottle or other containerabove the patient and thus provide gravitational infusion of the fluid.In such situations, which may occur during warfare, riots, or otherdisaster conditions, it is extremely advantageous to permit infusionwhile eliminating the necessity for a third person to carry the fluidcontainer.

One obvious technique for eliminating the noted problem involves theprovision of a structure mounted to the stretcher to support the fluidcontainer a predetermined height above the person being carried. In mostcases, this approach is either awkward or impossible. lt thereby becomesextremely important to provide suitable alternative means for carryingout such infusion, while, at the same time, eliminating the need for athird person to accompany the stretcher bearers or eliminating theawkward support assembly which must be secured to the stretcher.

SUMMARY OF THE INVENTION The present invention is characterized byproviding an infusion set which may be readily and simply attached to astretcher, or any other support or surface, which need not be elevatedabove the patient treated and, in fact, may be suspended a predetermineddistance below the patient or may simply be laid upon a hospital bed orstretcher alongside the patient, and which, at the same time, effectsfluid infusion at a substantially controlled and constant rate.

THe present invention comprises an assembly having at least first andsecond arcuate shaped highly resilient members adapted to receive acompressible fluidcontaining bag between their convex surfaces. Theresilient members are covered by suitable heavy-duty woven fabric sheetswhich further serve as pivoting means aligned along a pair of adjacentedges of the arcuate shaped sheets. The opposite free ends of the fabricsheets are provided with suitable fastening means adapted to retain thearcuate sheets in close proximity to one another so as to exert a largecompressive force upon the compressible fluid-containing bag positionedtherebetween. The force exerted upon the compressible bag by the arcuateshaped resilient sheets is of significant magnitude as to enable andprovide for fluid flow of a sufficient magnitude, regardless of therelative positioning between the infusion setand the body of the patientreceiving the sterile fluid, thereby enabling the bag to be supported ata height which is the same as or even below that of the patient, whilestill providing for adequate fluid flow from the compressible bag to thepatient, which flow may further be controlled by valve. and/ordripchamber means.

In accordance with a further feature of the invention, thepressure-applying device includes restraining means for limiting orpreventing lateral movement of the fluid-containing bag duringcompression thereof. Such means, which may comprise a sleeve forreceiving the infusion bag, a belt for winding about the bag, or simplyan adhesive surface for engaging the bag or the belt, frictionallyengages the infusion bag to prevent its expulsion from, and maintain itwithin, the pressureapplying means during compression thereof and thusfacilitate substantially continuous and uniform dispensing of the blood,saline solution or other fluid.

The basic components of an infusion set include the fluid container anda catheter or needle coupled thereto by suitable tubing. Thepressure-applying means of this invention is suitably employed incombination with these components and, typically, a stopcock or othervalve means and a drip chamber for regulating the flow of the fluidinfused. Whereas infusion sets provided in accordance herewith mayincorporate conventional catheters, drip chambers and stopcock elements,it is preferred that the drip chamber employed be of the type describedin my copending application entitled Drip Chamber For Infusion Set",Ser. No. 132,789, filed Apr. 7, 1971, now US. Pat. No. 3,721,689.

The infusion set described hereinabove is especially adapted for usein-military applications and is ideally suited for battlefieldconditions. The compressive forces developed by the arcuate shapedspringy members assure continuous, uniform infusion and further act toprevent cannula clogging and reverse flow. Upon appropriate operation ofthe valve means controlling flow, the contents of an infusion bag may berapidly emptied. For example, 1000 ml. may be infused through an 8X 5inch Fr. cannula within 10-12 minutes and through a 14 gallon needle inless than 5 minutes.

The compressive forces eliminate the need for a support normallyrequired for conventional gravity flow systems in that the structure iscapable of developing pressure equivalent to a head of cc. In use, thestructure permits easy transportation of casualties in battlefieldconditions as well as in ambulances, helicopters, planes or other air orground vehicles. Obviously, the versatility of the infusion set permitsits use under normal conditions such as exist in hospitals, clinicsandthe like. The infusion set is adaptable for use with all commerciallyavailable infusion bags (i.e., 400, 500 or 1000 ml.), is simple to userequiring no instruments or tools of either special or general purposedesign, is quite durable and is capable of being applied in an unlimitednumber of applications. The nature of the compressive structure is suchas to provide an extremely rugged, unbreakable device having anindefinite shelf-life under any climatic conditions, and having thefurther added feature of providing excellent protection from an infusionbag which may be stored therein, thus minimizing the risk of rupture orother damage, when, for. example, an infusion set incorporating the sameis dropped by parachute to a battlefield site or the like.

THE DRAWINGS The preceding and other objects and advantages of theinvention will become apparent from the following description taken inconnection with the accompanying drawings in which:

FIG. 1a.is a top plan view of an infusion apparatus embodying theprinciples of the present invention;

FIG. 1b is an end view of the embodiment of FIG.

FIG. 10 is a bottom plan view of the embodiment of FIG. 1a;

FIG. 1d is a sectional view of a portion of the infusion apparatus ofFIG. 1c looking in the direction of arrows 1d1d,'

FIG. la is an end view of the embodiment of FIGS. 1a 1c in the closed(operating) position and containing a compressible fluid bag;

FIG. If is an end view of the embodiment of FIGS. 1a 1c in the closed(storage) position;

FIGS. 2a and 2c are top and bottom plan view, respectively of another,preferred embodiment of the present invention;

- FIG. 2b is an end view of the embodiment of FIGS. 2a and2c, showingthe infusion assembly in the open position preparatory to use;

FIG. 2d is an end view of the embodiment of FIGS. 2a 2c showing theinfusion assembly in the closed (operating) position and containing acompressible fluid container;

FIG. 2e is a sectional view of a portion of the embodiment of FIG. 20looking in the direction of arrows 2e 2e;

FIG. 2f is an end view of another preferred embodi ment of the presentinvention;

FIG. 3 is a plot showing curves useful in explaining the advantages'ofthe present invention as compared with conventional gravity-flowtechniques.

THE PREFERRED EMBODIMENTS One preferred embodiment of the presentinvention is shown in FIGS. 2a 2e. Turning initially to a considerationof FIGS. 24 2c, the apparatus 100 shown therein is comprised of a pairof arcuate-shaped members 101 and 102 which consist of first and secondarcuate-shaped metallic plates 103 and 104, shown best incross-sectional view of FIG. 2b. The plates, in addition to beingarcuate in shape, have a high degree of resiliency so as to retain theirarcuate configuration in the absence of any external forces. Whereas theplates are described as being formed of metal, it should be understoodthat the plates may also be formed of a resilient plastic or othersuitable material.

The plates 103 and 104 are covered on both surfaces thereof, as well asalong their perimeters, with a heavy duty fabric such as, for example, aheavy canvas material. As shown best in FIG. 2b, one continuous piece offabric, comprised of top portions 105a and 105b, covers the convexsurfaces of metallic sheets 103 and 104, respectively. The concavesurfaces are also covered by the single sheet of fabric, wherebyportions 106a and l06b are folded around the edges of plates 103 and 104to cover the concave surfaces of sheets 103 and 104, respectively. Thefabric sheets are joined to one another along the remaining portions ofthe perimeter of each of the metallic plates 103 and 104, preferably bybeing sewn together.

Noting FIG. 2b, sheet portion 105a has its extreme left-hand edgesurrounding the left-hand edge 1030 of plate 103. Lower sheet portion106a is bent inwardly upon itself, as shown at 106a, with the; twosheets being sewn together, as shown at 107. The fabric sheet portions105b and 106b are joined together about the remaining perimeter ofmetallic sheet 104 in a similar fashion and are sewn together alongtheir engaging margins at the location shown by the numeral 1061).Sheets 105a and l05b terminate at the center line of the structuredesignated by phantom line 108 and are folded under, as shown at 105aand l05b'. The metallic rivets 109 pierce these fabric sheet portionsand metallic sheets and act to firmly secure the heavy-duty fabric tothe arcuate shaped metallic sheets. The rivets 109 are shown best in thetop view of FIG. 2a which shows the convex surfaces and the bottom viewof FIG. 20 which shows the concave surfaces of the pair of arcuateassemblies 101 and 102.

Assemblies 101 and 102 are of equal length and have their free endsrespectively tapered, at 110 and 110a. A heavy-duty woven fabric belt111 is joined to arcuate assembly half 102 by means of rivets 102.Although not shown for purposes of simplicity, belt 111 is substantiallyan elongated member and, in one actual embodi ment, has a length ofapproximately 20 inches.

A buckle assembly 113 is mounted to assembly half 101 and is comprisedof a short section 114 of a heavy duty woven fabric belt secured toassembly half 101 by rivets 115. The free end of the short belt portion114 is secured between a slightly curved metallic sheet 1 l6 and anarrow, elongated metallic sheet 117 by means of rivets 118. Theslightly arcuate shaped metallic sheet 116 is provided with a pair ofears 118 and 119 which are bent to surround a rod 120 secured at itsopposite ends to a rectangular-shaped buckle member 121. The left-handend of slightly arcuate shaped member 116 is provided with a serratededge 122 which cooperates with the buckle member 121 to lock beltportion 111 which has passed through the region designated by dottedline 1 11 so as to retain the assembly in the infusion state, which willbe more fully described hereinbelow.

As can best be seen from FIG. 2c, the short belt section 114 is securedbetween a narrow, elongated plate 123 and assembly half 101 by therivets 115. The belt extends further to the right of plate 123 and islooped over itself to form a narrow opening for a substantially C-shapedclip 124 whose free ends 1240 and 124b extend into the opening formed inbelt portion 114.

. The looped over belt portion is sewn to the remaining belt portion, asshown by dotted lines 125. Clip 124 is further provided with a secondclip 126 which may be utilized to releaseably support or hang theinfusion bag assembly upon a belt loop, or any other structure for thatmatter, to facilitate either carrying or actual usage of the assembly.

The belt 111 is provided with a similar overlapped portion which isretained against the main body of the belt by sewing the two portionstogether, as designated by dotted lines 127. The bent-over portion ofthe belt provides a narrow opening for receiving the free ends 128a and128b of a second clip 128 which, in turn, is

provided with an additional clip 129 for releaseably mounting theassembly to any suitable structure or to a belt loop field pack, or anyother apparatus. Belt 111 is secured between assembly half 102 and anelongated metallic plate 130 by means of the rivets 112.

FIG. 2e is a sectional view of a portion of assembly half 102 looking inthe direction of arrows 2e2e and shows the manner in which the fabricsheets are joined together along the lower edge. Metallic sheet 104 ispositioned between the fabric sheets 106b'and 105b. The marginal edge offabric sheet 105b is bent under, while the marginal portion of fabricsheet 1061; is bent around the marginal edge of metallic sheet 104. Theengaging marginal portions are sewn together at 131. The perimeters ofboth assembly halves 101 and 102 have their fabric sheets joinedtogether in a similar fashion.

FIG. 2b shows the assembly as being further provided with a retainingmeans comprising a pair of sleeves 132 and 133 for retainingcompressible bags of fluids which may, for example, be blood plasma, orany other sterile fluid which is to be infused into the body of apatient. The sleeves are formed from a single sheet of heavyduty wovenfabric material 134. One free end 134a of the single sheet is secured toassembly half 102 by means of the rivets 109. The sheet extends awaytherefrom to first form the left-hand side, top side and righthand sideof sleeve 132. The sheet then extends upwardly to form the left-handside, top side and righthand side of sleeve 133, with the extreme freeend l34b extending beneath point 135 where the right-hand side of sleeve132 and the left-hand side of sleeve 133 share a common boundary. Thesingle sheet is then sewn together at location 136. The thread employedto sew the single sheet of fabric 134 to itself is also further sewnthrough the center line of the single sheet comprised of sheet halves106a and 106b along the line coincident with the central axis 108 of theassembly. If desired, one end of each sleeve may then be sewn closed toform corresponding pockets.

It should be noted that sleeve 132 is larger than sleeve 133 so as toaccommodate a compressible plastic bag of larger size (and hence,volume). For example, sleeve 133 may be adapted to-accommodate acompressible plastic bag of sterile fluid having a capacity of 500milliliters, while sleeve 132 may be adapted to receive a compressibleplastic bag having a capacity of 1000 milliliters. The sleeves (132 or133) serve to retain a compressible fluid bag between the arcuate plateswhile during the time the plates are moved to the operating position.The manner of use of the sleeves is as follows:

The compressible bag is inserted into the sleeve whose opening isclosest in size to the compressible fluid bag. Once the fluid bag isinserted, the free ends of springy plates 103 and 104 are moved from theposition substantially as shown in FIG. 2b to the position shown in FIG.2d. Closure and locking of the plates is accomplished by drawing belt111 (see FIG. 2d) through buckle assembly 113. Although the closing ofthe plates 103 and 104 would otherwise tend to urge the compressible bagout from between the plates, the sleeve prevents this from occurring.

One alternative arrangement to the sleeves 132 and 133 which may beemployed is shown in FIG. 2f and is comprised of an elongated strap 140having a first end thereof 141 sewn or otherwise secured to assemblyhalf 101. The marginal portion of the free end of strap may be providedwith a strip 142 of an adhesive material which may be releaseablysecured to surface portion 143 provided along the convex surface ofassembly half 102 in close proximity to the center line 108 of theassembly. As another alternative, a VELCRO fastener assembly may beemployed, wherein the strip 142 may be comprised of the loop portion ofa VELCRO fastener, while the strip 143 may be comprised of the hookportion of a VELCRO fastener so as to releaseably join strap 140 tosurface 143. As is well known with regard to VELCRO fasteners suchassemblies, when joined together, are capable of remaining joinedtogether even in the presence of great shearing stresses which may beexerted thereupon. I

In use, the compressible bag of sterile fluid 145 is positioned betweenthe two convex surfaces of assembly halves 101 and 102. Strap 104 ispositioned around the bag 145 in the manner shown best in FIG. 2f. Thestrip 142 provided near the marginal end of strap 140 is then pressedagainst strip 143 so as to secure the compressible bag 145 and preventthe bag from moving in the direction shown by arrow 146. The free end ofbelt 111 is threaded through the buckle assembly 113 in the manner shownin FIG. 2f, and is then pulled in the direction shown by arrow 147 todraw the outermost edges 101a and 102a of assembly halves 101 and 102toward one another until the two outermost edges are either in closeproximity or engage one another. The resilient arcuate shaped metallicsheets 103 and 104 exert a counter-force which tends to urge theinfusion assembly halves 101 and 102 apart. However, the belt 111, inattempting to be pulled away from the buckle assembly 113, engages theserrated edge 122 of plate 116 so as to remain tightly fastened orwedged between the serrated edge 122 and buckle member 121 to preventthe assembly halves from moving apart.

The resilient metallic sheets thereby exert significant force upon thesurfaces of the compressible bag of sterile fluid to cause the sterilefluid to be urged out of the bag through (see FIG. 2d) a piece of hollowtubing 148, valve 149, drip chamber and tubing 151, whose free end isprovided with a suitable hypodermic needle 152 which may be insertedinto the body to infuse the fluid into the body of the patient. Valveassembly 149 may be employed to selectively cut off or enable fluidflow, while drip chamber assembly 150 may be utilized to regulate therate of flow.

The manner of use of the embodiment of FIG. 2b is substantially similarto that shown in FIG. 2f, except that the compressible bag of fluid isfirst inserted into the appropriate sleeve 132 or 133. The free end ofbelt 111 is then inserted through the buckle assembly in similar fashionto that described hereinabove to draw the outer ends of assembly halves101 and 102 together so as to exert a significant compressive force uponthe compressible plastic bag of sterile fluid.

The primary and significant feature of the infusion bag assembly residesin the fact that the assembly need not be positioned above the body ofthe patient so as to rely upon gravity to insure flow of the fluid fromthe bag or sterile container into the body. For example, in battlefieldsituations, it may be quite impractical, if not impossible, to mount acontainer of sterile fluid upon a stretcher, whereby the container ofsterile fluid is positioned well above the height of the person beingcarried. With the present invention, the infusion bag assembly may evenbe mounted at or below the height of the person being carried ortreated, since the relatively large compressive forces of the assemblyare more than sufficient to squeeze the sterile fluid from the bag andinto the body of the patient. Accurate regulation of fluid flow may becontrolled through the use of valve 149 and drip chamber 150, or throughthe use of any other suitable flow-regulating means.

FIG. 3 shows curves comparing the flow rate through the infusion set ofFIGS. 2a-2c. As shown in FIG. 3, Curve A represents the infusion orexpelling of a saline solution contained in a 1000 ml bag for anapparatus as shown in FIGS. 2a-2c which is located at the same height asthe catheter. The curve indicates that the en- ,tire contents areexpelled in 12 minutes. Curve B represents the flow rate for an infusionset of the type shown in FIGS. 2a-2c which is located at a height of onemeter above the catheter level. It can be seen that the entire contentsare expelled within nine minutes.

Curve C represents the flow rate for a sterile fluid bag elevated at aheight of one meter above the catheter level and in the absence of theinfusion set hereof. It can be seen that 16 minutes are required toexpel the entire contents of the fluid container. Similar results havebeen obtained for other solutions such as, for example, a dextrinsolution from which the entire contents of a 560 ml fluid container areexpelled within 11% minutes, while 17 minutes are required to expel theentire contents of a bag positioned at one meter above the catheterlevel in the absence of the nongravitational infusion set. The entirecontents of a 560 ml container can be expelled within 9 minutes when theinfusion set of FIG. 2a-2c is positioned one meter above the catheterlevel. Similar results have been obtained for other fluids, includingblood.

When not in use, the assembly 100 may be made quite compact by threadingthe belt 111 through the buckle assembly 113 in a manner similar to thatdescribed above, with the exception that no compressible bag of fluid beinserted between the assembly halves 101 and 102. The assembly 100 maythen be carried in any suitable mmanner such as inside of a field pack,clipped to the exterior of a field pack, or clipped to a waist belt orany other suitable place or location.

The assembly 100, which is formed of a very heavyduty fabric and aheavy-duty buckle assembly and fabric belt, is relatively indestructibleand have an extremely long, useful operating life. In addition, theeffectiveness of the assembly 100 will not be reduced or significantlyaltered as a result of exposure to outside elements or influences, suchas rain, sleet, snow, salt water, dirt, dust, or any other influenceswhich may normally be considered to be harmful. The arcuate shapedmetallic sheets, in one preferred embodiment, are preferably formed froma springy, resilient steel, and it has been found that no significantreduction in effectiveness of the plates has occurred even aftercontinued use, regardless of the conditions or situations in which theassembly is used.

FIGS. la-lf show another preferred embodiment 10 of the presentinvention, which is comprised of a plural ity of arcuate shaped metallicsheets 11 (a total of eight being employed in the assembly shown inFIGS. la and 1c, for example). The assembly half 12 utilizes four of thearcuate shaped metallic sheets which are arranged in side-by-sidefashion and inserted within separate sleeves l3l6, which sleeves areformed from a pair of heavy-duty woven fabric sheets 17 and 18, whichare sewn together along the top, bottom and right-hand edges of assembly12 and are further sewn along lines 19, 20 and 21 so as to form fourindividual sleeves which are open along their left-hand edges to permitinsertion of each of the associated arcuate shaped rnetallic sheets 11.

The metallic sheets 11 are each retained within their associated sleevesby rivets 22. The rivets 22 further serve to secure onecooperatingportion of a clasp assembly, which portions are designated bythe numerals 23a-23d, respectively. Since the clasp portions 23a-23a'are substantially identical in design and function to one another, onlyone such assembly will be described herein for purposes of simplicity.

Considering assembly 23a, this clasp portion can be seen to be comprisedof a mounting bracket 24 having a pair of mounting portions 2441-2412(see FIG. 1b), which portions are joined to sleeve 13 by rivets 22.Mounting portions 24a and 24b are integrally joined to one another bymeans of a yoke portion 24c, which yoke portion forms an opening forreceiving the free ends 25a and 25b of a clasp membler. Clasp member 25is free to pivot about the yoke portion in either direction, as shown bythe double-headed arrow 26 of FIG. lb.

The remaining half 12' of infusion bag assembly 10 is formed of twoheavy-duty fabric sheet members 17 and 18' similar to those describedhereinabove, which sheets are joined or sewn together so as to form theseparate sleeves 13'16, each of which receives one of the arcuate-shapedmetallic plates 11.

Assembly half 12 is provided with four clasp portions 27a-27d, each ofwhich cooperate with an associated clasp portion 23a-23d, respectively,in a manner to be more fully described. Since each of the clasp portions27a-27d are similar in design and function, only one will be describedherein for purposes ofsimplicity.

The assembly 27a is comprised of a mounting bracket 28 having a pair ofsimilar mounting halves 28a and 28b secured to sleeve 13' by rivets 22.The mounting portions 28a and 28b are integrally joined to one anotherby a yoke portion 28c which has a substantially triangular shapedconfiguration, as can best be seen from FIG. lb, so that the headportion may be snappingly received by the associated buckle 25, in amanner to be more fully described.

The manner in which the infusion bag assembly 10 is put into use is asfollows:

A compressible plastic bag of sterile fluid is positioned between theconvex surfaces of assembly halves l2 and 12 in the manner shown best inFIG. 1b. Halves 12 and 12 are then moved toward one another in thedirections shown by arrows 29a and 2912 until the outer free ends ofassembly halves l2 and 12' are brought into engagement. Each of thebuckles 25 is then snapped over its associated head 280 where they remain locked in the position shown best in FIG. 1e. The highly resilientarcuate shaped metallic members exert a relatively high compressiveforce against bag 145 to squeeze the fluid from the bag and preferablythrough the valve, drip chamber and injection or hypodermic needleassembly of the type shown best in FIG. 2d. It should be understood thatall four clasp assemblies are locked into position in the manner shownbest in FIG. 12.

For a device of the type similar to that shown in FIGS. la-lc comprisingthree pairs of curved, springy, metallic sheets (formed by cutting acylinder of metallic material in half and by cutting each of the halvesinto three parts), the initial pressure applied to a com pressible fluidbag was 0.15 atmospheres (equal to about 1.5 meters of water) whichyielded a flow rate of approximately 100 ml per minute at the initialstages, which flow rate decreased to about 70 ml per minute near the endof the infusion.

The use of separate arcuate shaped metallic sheets in each half 12 and12 of the assembly as opposed to the use of only a single arcuate-shapedmetallic sheet as in the case of assembly 100 of FIG. 2, for example,facilitates locking of the clasp assemblies, since the arcuate shapedmetallic sheets of significantly smaller size individually exert smallercounteracting forces, thereby making it easier to latch each of theindividual clasps.

Although not shown for purposes of simplicity, the assembly of FIGS.la-lfmay be provided with a releaseable clasp or other hardware forsuspending the infusion bag assembly 10 from a stretcher or a fieldpack, for example, either during use or while being transported.

FIG. 1d, which is a sectional view of a portion of the assembly shown inFIG. lc taken along the lines 1d 1d, shows the manner in which thefabric sheets are sewn together. Fabric sheet 18 has its marginal edgefolded around the marginal edge of the arcuate metallic sheet 11. Fabricsheet 17 has it marginal portion folded under so that the two engagingportions may be sewn as shown at the location designated by numeral 31.The fabric sheets are further sewn together as shown by numeral 21 toform the two separate sleeves l6 and 15, each of which is adapted toreceive one of the arcuate shaped metallic resilient sheets 11, 11. Theremaining peripheral portions of the assembly halves l2 and 12' are sewntogether in a similar fashion.

When not in use, the assembly 10 may be made quite compact either bydrawing the two concave surfaces toward one another in the manner shownin FIG. 1f or, alternatively, by bringing the two convex surfaces towardone another in the manner shown in FIG. 12, with the exception that nocompressible sterile fluid bag is inserted therebetween. The clasps arethen joined either in the manner shown in FIG. 1f, or in the mannershown in FIG. 1e to render the assembly quite compact during eitherstorage or transportation thereof. If desired, a compressible bag may bestored between the members 12 and 12' when in the position of FIG. If.The plates exert only a mild force upon the compressible fluid bag so asnot to stress the bag when not in use. The distinct advantage of storingcompressible bags in this manner is to protect the compressible bagduring storage, handling or transportation. The embodiment of FIG. 2 maybe utilized in a similar'fashion.

As another obvious alternative, the assembly 10 of FIGS. la-lf may beprovided with a strap of the type shown in FIG. 2e, or one or moresleeves of the type shown in FIG. 2b to facilitate retention of thecompressible sterile fluid bag between the convex surfaces of theassembly halves l2 and 12 so as to retain a compressible fluid bagbetween the assembly halves when they are moved to the position of FIG.1e.

As another possible alternative to the preferred embodiments of thepresent invention, any other suitable hinge means may be employed forpivotally connecting the curved, springy, metallic sheets in addition tothe employment of the heavy-duty fabric sheets as the means forpivotally connecting the metallic sheets.

- It can be seen from the foregoing description that the presentinvention provides a novel non-gravitational infusion bag set forsqueezing sterile fluid, and the like, from a compressible fluid bag,wherein the assembly is quite compact to facilitate storage andtransportation, while having a unique design to enable infusion ofsterile fluid, and the like, from a compressible bag in anongravitational manner, thus eliminating the need for mounting orsupporting the sterile fluid container a significant distance or heightabove the body of the patient, as is required in conventional infusiontechniques which primarily rely upon gravitational flow. The assembly isthus uniquely adapted for use in situations in which fluid flow bygravity is either impractical or impossible, such as, for example, theuse in battlefield, riot or other disaster conditions which restrict orotherwise render impossible the infusion of a fluid into a patientthrough normal gravity flow techniques.

Although this invention has been described withrespect to particularembodiments, it should be understood that many variations andmodifications will now be obvious to those skilled in the art, and,therefore, the scope of this invention is limited not by the specificdisclosure herein, but only by the appended claims.

What is claimed is:

1. An assembly for exerting pressure upon a compressible fluidcontainer, comprising:

a. a pair of curved resilient plates having respective inner and outerplanar edges extending transversely of the curvature thereof;

b. hinge means for hingedly mounting said inner edges of the plates toone another in substantial parallelism for pivotal movement of theplates into facing relation with the convex surfaces of the platesfacing one another;

c. clasp means mounted along said outer edges of the plates for securingsaid edges to one another and thereby holding the plates in closeproximity to one another with the convex surfaces thereof adapted toapply pressure to a compressible fluid container positioned between saidplates;

d. restraining means for limiting movement of the compressible fluidcontainer transversely of said first and second plate edges tofacilitate compression of the container and dispensing of the fluidtherefrom by said assembly;

e. said restraining means comprises a hollow sleeve secured to saidsheath in the region of said hinge and along the concave side of saidplates for receiving a compressible fluid bag to prevent movement ofsaid bag when said plate halves are being moved to the operatingposition.

2. The assembly of claim 1, wherein said restraining means furthercomprises a plurality of hollow sleeves of different diameters securedto said sheath in the region of said hinge and along the concave side ofsaid plates for receiving compressible fluid bags of varying sizes, eachof said sleeves preventing movement of the bag received therein as saidplate halves are moved to the operating position.

1. An assembly for exerting pressure upon a compressible fluidcontainer, comprising: a. a pair of curved resilient plates havingrespective inner and outer planar edges extending transversely of thecurvature thereof; b. hinge means for hingedly mounting said inner edgesof the plates to one another in substantial parallelism for pivotalmovement of the plates into facing relation with the convex surfaces ofthe plates facing one another; c. clasp means mounted along said outeredges of the plates for securing said edges to one another and therebyholding the plates in close proximity to one another with the convexsurfaces thereof adapted to apply pressure to a compressible fluidcontainer positioned between said plates; d. restraining means forlimiting movement of the compressible fluid container transversely ofsaid first and second plate edges to facilitate compression of thecontainer and dispensing of the fluid theRefrom by said assembly; e.said restraining means comprises a hollow sleeve secured to said sheathin the region of said hinge and along the concave side of said platesfor receiving a compressible fluid bag to prevent movement of said bagwhen said plate halves are being moved to the operating position.
 2. Theassembly of claim 1, wherein said restraining means further comprises aplurality of hollow sleeves of different diameters secured to saidsheath in the region of said hinge and along the concave side of saidplates for receiving compressible fluid bags of varying sizes, each ofsaid sleeves preventing movement of the bag received therein as saidplate halves are moved to the operating position.